Projects

Phase II Site Assessment

Redondo Beach, California

Background

McAlister GeoScience was retained to conduct a Phase II Environmental Site Assessment (ESA) consisting of soil sampling for a property located in Redondo Beach California (the Subject Property).  

The purpose of the soil sampling and analysis project was to document the nature and extent of potential soil impacts associated with the operation of the Subject Property as a furniture refinishing facility including the storage, use, and disposal of hazardous materials including paints, solvents, and wood stains.  

McAlister GeoScience conducted a Phase I ESA prior to the performance of the Phase II ESA while the property was occupied by a furniture stripping and refinishing business.  The Phase I ESA recommended comprehensive soil sampling at the Subject Property with analysis of the soil samples collected for volatile organic compounds (VOCs), total petroleum hydrocarbons, and metals associated with aqueous stripping compounds, varnishes, paints, and furniture finishing substances.

A total of seven soil samples were collected from each of the seven borings advanced in areas of hazardous material storage, use, and disposal at the Subject Property.  Following sample collection, the borings were backfilled with native soil and surface patched with dry mix concrete to match the existing surface conditions. Samples were submitted to an analytical laboratory for analysis.

Results

Concentrations of VOCs and Total Petroleum Hydrocarbons were present in all seven soil samples collected above the laboratory detection limits in the areas of hazardous material storage, use, and disposal at the Subject Property.  Boreholes were advanced to the depth of refusal ranging between six and eight feet below ground surface.

Volatile organic compounds with analytical detections above their respective EPA Region 9 Regional Screening Levels included Benzene, Methylene Chloride, Tetrachloroethylene (PCE), 1,2,4-Trimethylbenzene, 1,2,5-Trimethylbenzene, and Xylenes.  The ground surface a the Subject Property is entirely covered with asphalt or concrete paving ruling out the risk of dermal contact or ingestion for personnel at the Subject Property. Volatile organic compounds present in soil present a potential vapor intrusion risk, depending on the permeability of the concrete or asphalt ground surface.  

McAlister GeoScience recommended that if the property were to be converted to residential, sensitive receptor, or any land use other than commercial / industrial, the concentrations of VOCs, TPH, and Metals should be re-evaluated for the specific land use(s).

Based on the information gathered during the performance of this assessment, and the understanding of current regulatory guidelines and judgment, it was recommended that indoor air samples be collected once the current tenant ceases operations and removes the currently existing hazardous material storage, use, and disposal areas.  The purpose of the indoor air sampling was to document that concentrations of VOCs present in soil underlying the structure do not create concentrations of VOCs in the air within the building above regulatory screening levels or OSHA exposure limits.